Frequently a patch is needed to isolate worn casing or a liner string needs to be inserted in casing and expanded into a sealing and supporting relationship with the surrounding tubular. Many times the specific dimensions of the surrounding tubular or the surrounding wellbore are unknown and the time and expense it takes to figure out the internal dimensions where the cladding or liner in what's known as a gauge run is not within the plans or budget of the well operator. The problem arises when the cladding is to be expanded with a fixed swage or a variable swage whose outer dimensions are not known to be sufficiently large to properly locate the cladding for sealing support in the wellbore or surrounding tubular.
Various techniques have been use to engage a seal between one tubular and a surrounding one. Some have employed the hanging weight of one tubular to energize a seal with the surrounding tubular. Some examples of such designs are U.S. Pat. Nos. 5,031,695; 5,031,696; 5,799,730 and 6,488,084. Other design employed explosive force or swaging such as U.S. Pat. Nos. 4,662,450 and 6,390,201. U.S. Pat. No. 6,098,717 shows the use of external seals on the inner tubular to be expanded into contact with the surrounding tubular for contact upon expansion.
What is lacking in the prior designs is an exterior treatment for the inner tubular that is compliant to adjust to the variability in inside dimensions to be encountered with the surrounding tubular or wellbore while at the same time being able to provide adequate support for loads in opposed directions and/or some interaction between a sealing member and the anchoring feature that preferably penetrates the outer tubular or wellbore wall. Those skilled in the art will better appreciate the scope of the invention from a review of the description of the preferred embodiment and the drawings, which appear below.